1. Field of the Invention
The present invention relates to a character display apparatus and a character display method capable of displaying a character with a high definition using a color display device, and a recording medium for use with such apparatus and method.
2. Description of the Related Art
As a method for emphasizing a certain region of sentences on display, adding a color to characters, blinking characters, etc., are known.
In the conventional method for emphasizing a certain region of sentences by adding a color to characters, the characters are displayed in a single color. Such a display is conspicuous, but the color tone thereof is harsh, and therefore, the displayed characters are difficult to read. Moreover, in the conventional method for emphasizing a certain region of sentences by blinking characters, the characters vanish for a certain period of time. Thus, such a display is difficult to read, and tires an eye of a viewer.
On the other hand, the Applicant of the present application has developed techniques for displaying characters with a high definition by controlling the brightness of a color display device on a sub-pixel by sub-pixel basis. (These techniques are disclosed in Japanese Patent Application No. 11-024450, Japanese Patent Application No. 11-112954, and Japanese Patent Application No. 11-214429.) As an application of these techniques, the Applicant of the present application also developed a technique for adding a color to characters or to a background of characters.
According to one aspect of the present invention, a character display apparatus includes: a display device having a plurality of pixels; and a control section for controlling the display device, wherein: each of the pixels includes a plurality of sub-pixels arranged along a predetermined direction; a corresponding one of a plurality of color elements is pre-assigned to each of the sub-pixels; an intensity of each of the color elements is represented stepwise through a plurality of color element levels; the control section executes tasks of: setting each of the sub-pixels to one of the color element levels; according to a relationship between the plurality of color element levels and a plurality of brightness levels, converting the color element level for each of the sub-pixels to a corresponding brightness level among the plurality of brightness levels; and changing the relationship according to at least one of character color information which defines a color of a character to be displayed on the display device and background color information which defines a background color of the character.
In one embodiment of the present invention, the character color information includes information representing a color type of the character; and the control section changes the relationship according to the information representing a color type of the character.
In another embodiment of the present invention, the character color information further includes information representing a color darkness of the character; and the control section changes the relationship according to the information representing a color type of the character and the information representing a color darkness of the character.
In still another embodiment of the present invention, the character color information includes information representing a background color type of the character; and the control section changes the relationship according to the information representing a background color type of the character.
In still another embodiment of the present invention, the character color information further includes information representing a background color darkness of the character; and the control section changes the relationship according to the information representing a background color type of the character and the information representing a background color darkness of the character.
In still another embodiment of the present invention, the relationship is determined based on one or more parameters; and at least one of the one or more parameters is a function of time.
In still another embodiment of the present invention, the control section changes the relationship according to character reverse information which determines whether or not the color type of the character and the background color type of the character are replaced with each other.
According to another embodiment of the present invention, a character display method for displaying a character on a display device having a plurality of pixels, wherein: each of the pixels includes a plurality of sub-pixels arranged along a predetermined direction; a corresponding one of a plurality of color elements is pre-assigned to each of the sub-pixels; an intensity of each of the color elements is represented stepwise through a plurality of color element levels; the character display method includes steps of: setting each of the sub-pixels to one of the color element levels; according to a relationship between the plurality of color element levels and a plurality of brightness levels, converting the color element level for each of the sub-pixels to a corresponding brightness level among the plurality of brightness levels; and changing the relationship according to at least one of character color information which defines a color of a character to be displayed on the display device and background color information which defines a background color of the character.
According to still another embodiment of the present invention, a recording medium which can be read by an information display apparatus, the apparatus including a display device having a plurality of pixels and a control section for controlling the display device, wherein: each of the pixels includes a plurality of sub-pixels arranged along a predetermined direction; a corresponding one of a plurality of color elements is pre-assigned to each of the sub-pixels; an intensity of each of the color elements is represented stepwise through a plurality of color element levels; the recording medium includes a program which causes the control section to execute steps of: setting each of the sub-pixels to one of the color element levels; according to a relationship between the plurality of color element levels and a plurality of brightness levels, converting the color element level for each of the sub-pixels to a corresponding brightness level among the plurality of brightness levels; and changing the relationship according to at least one of character color information which defines a color of a character to be displayed on the display device and background color information which defines a background color of the character.
Hereinafter, functions of the present invention will be described.
According to the present invention, the relationship between the color element level of each sub-pixel and the brightness level of the sub-pixel is changed according to at least one of character color information and background color information. Therefore, characters can be displayed with a high definition by controlling the brightness of a display device on a sub-pixel by sub-pixel basis while a color is added to the characters or to a background of the characters.
Further, a color can be added to a character while a skeleton portion (i.e., core structure) of the character, which represents core lines of strokes of the character, is kept black. Therefore, the color contrast between adjacent characters can be suppressed. As a result, characters which are not harsh and which are easy to read can be displayed so that the characters do not tire an eye of the viewer.
Furthermore, a certain area of a displayed sentence can be emphasized by changing a background color of characters. Moreover, by replacing a color of a character and a background color of the character with each other, a brighter character can be displayed so that the character can be easily viewed.
Still further, by changing the relationship between the color element level of a sub-pixel and the brightness level of the sub-pixel along with the passage of time, a color of a character or a background color of a character can be changed along with the passage of time, whereby the character can be emphasized. Such an emphasizing method prevents a character from vanishing as would occur when a character is emphasized by blinking. Thus, it is possible to provide a pleasant display which is easy for a human eye to observe.
Thus, the invention described herein makes possible the advantages of (1) providing a character display device and a character display method capable of adding a color to characters or a background of characters while displaying the characters with a high definition by the control on a sub-pixel by sub-pixel basis, and a recording medium for use with such apparatus and method, and (2) providing a character display device and a character display method capable of emphatically displaying characters so that the displayed characters do not tire a human eye, and a recording medium for use with such apparatus and method.
These and other advantages of the present invention will become apparent to those skilled in the art upon reading and understanding the following detailed description with reference to the accompanying figures.